The present invention relates to an AC adapter plug to be releasably insertable in electrical wall outlets, and more particularly to such an adapter plug which has pins which are convertible to fit into different types of electrical wall outlets as may be found, for example, in different countries.
AC plugs to which the present invention is directed, comprise an electrically insulative body within which are secured separate conductive terminals to which AC wires are connected. The plug has spaced, electrically conductive, flat, elongated pins which are in permanent electric contact with the terminals within the plug. These pins extend outwardly at a 90.degree. angle from a flat base of the plug, the pins being releasably insertable into correspondingly aligned sockets of electrical wall outlets.
One problem experienced frequently by travellers from one country to the other is that the sockets of the electrical wall outlets for such flat pin plugs may be differently aligned from country to country. For example, in North America, the flat pins extend outwardly from the plug base with flat surfaces facing each other and lying in parallel planes. In countries such as Australia, while the pins are essentially spaced a similar distance from each other, they are angled with respect to each other so that their planes intersect at about a 60.degree. angle.
This means that appliances made for North America, if used by a traveller in Australia, require an adapter plug having one surface with sockets to receive the parallel, North American pins, and the opposite surface having extending therefrom the angled, Australian-type pins. Similarly, electrical appliances made for Australia, if used in North America, must have a different type of adapter having on one surface angled sockets to receive the angled pins of the Australian-type plug and parallel pins extending outwardly from the other surface to go into the sockets of North American wall outlets.
Convertible adapter plug devices intended to simplify these and related problems are known. For example, Flohr U.S. Pat. No. 4,856,999 issued Aug. 15, 1989 describes and illustrates an electric adapter having a body in the form of a straight, five-sided prism, each of the sides of which has a different pin configuration for differing configurations of sockets of electrical wall outlets.
Thomas U.S. Pat. No. 1,249,247 issued Dec. 4, 1917 teach convertible plugs in which the pins are pivotably secured by screw means to the terminals within the plug bodies and rotatable to different configurations.
Aarlaht Canadian Patent No. 628,684 issued Oct. 10, 1961 teaches a convertible plug in which the pins are rotatable about an axis and held in position by a slotted closure plate which must be removed to permit rotation of the pins and replaced to hold the pins in position.
Erickson et al U.S. Pat. No. 4,815,983 issued Mar. 28, 1989 and Hubbell Canadian Patent No. 660,492 issued Apr. 2, 1963 describe and illustrate more complicated constructions of adapter plugs permitting alternative arrangements of pins for different purposes.
Helmich, Jr. U.S. Pat. No. 4,911,649 issued Mar. 27, 1990 is of general background interest being directed to an adaptable wall outlet.
It is an object of the present invention to provide a simple and economical construction of AC adapter plug which will permit conversion of the same plug to either North American or Australian type pin arrangements.